#include "common.h"

class Solution
{
public:
    int findPeakElement(vector<int> &nums)
    {
        int left = 0, right = nums.size() - 1;
        while(left < right)
        {
            int mid = left + (right - left) / 2;
            // mid 下标一定合法
            if(mid < nums.size() - 1 && nums[mid] > nums[mid + 1])
            {
                right = mid;
            }
            else if(mid < nums.size() - 1 && nums[mid] < nums[mid + 1])
            {
                left = mid + 1;
            }
        }
        return left;
    }
};